Almost one in five children across the Canterbury district start school either overweight or obese.

Startling figures from the National Child Measurement Programme for England reveal 9.8% of four and five-year-olds are overweight, while a further 9.7% are obese.

The statistics, based on children from all state schools, have prompted Public Health England to call for urgent action.

Health Secretary Jeremy Hunt said he would ensure the “great scandal” of childhood obesity was one of his main priorities, but campaigners criticised last year’s childhood obesity plan – which included the controversial ‘sugar tax’ – for being heavily watered down.

Allison Duggall, KCC deputy director for public health, said: “Obesity tends to track into adulthood, so obese children are more likely to become obese adults. The best way to tackle obesity is to eat a healthy, reduced-calorie diet and to exercise regularly.

“Our local priorities focus on changeable factors such as helping families to improve poor diets and help for those who need to lose and maintain a healthy weight.

“We also have evidence that Kent’s adult population is becoming more inactive and it’s imperative that we act early to raise awareness of the services available and support people to change their behaviours.

“This includes backing campaigns like Sugar Smart and encouraging school programmes that promote a healthy lifestyle.”

Gravesham has the second highest level of childhood obesity in the south east, with 28% overweight or worse.

The national average is 22.6%, while the worst-performing area in the country is Barrow-in-Furness in Cumbria, with 31.5%.